Field of the Invention
The present invention relates to a semiconductor device provided with high humidity resistance.
Background Art
Rapid progress is being made in universal use of high-frequency semiconductor devices typified by field-effect transistor elements using compound semiconductors such as GaAs, GaN. Regarding high frequency semiconductor devices, there has been no need to consider influences of water from an external environment so far by maintaining a high level of hermeticity inside packages in which the semiconductor devices are mounted. However, in recent years, since package mounting is performed using low-priced plastic mold materials, cost reduction is increasingly being achieved. Since it is difficult to prevent permeation of water into plastic mold materials, how to secure humidity resistance of semiconductor devices is becoming an important factor in securing reliability of products.
A semiconductor device is proposed in which a guard ring is constructed of a conductive semiconductor in a peripheral region of a semiconductor device and part of the guard ring is exposed from an insulating film (e.g., see (FIG. 7 and FIG. 8, p. 29 of) Japanese Patent Application Laid-Open No. 2008-227116).